1. Field of the Invention
The present invention relates generally to determining the degree of contamination of oil. More particularly, the present invention relates to a monitor sensor and system for monitoring the accumulation of contaminants in engine oil.
2. Description of Related Art
Oxidation products, such as water and sulfuric acid, accumulate in motor oil during operation of the engine. The build-up of these contaminants can corrode the internal surfaces of the engine. Since these contaminants are not removed by conventional filtration methods, the oil must be changed when the levels of these species increase beyond acceptable limits. Prolonged operation of an engine having high levels of contaminants in the oil can lead to premature engine failure or other corrosion related problems.
Currently, the lifetime of engine oil is usually determined according to mileage or time limits wherein the oil is automatically replaced after established limits are reached. Such mileage or time limits are based on operation of the engine under normal operating conditions and operation within normal limits. The problem with such established oil change schedules is that contaminants may build up at a higher or lower rate depending upon the operating environment of the engine. As a result, the engine may be subjected to unduly high contaminant levels or on the other hand, oil may be wasted due to unneeded replacement when contaminant concentrations are still below acceptable levels.
It would be desirable to provide a system for continually monitoring the contaminant concentrations in engine oil to provide a constant measure of engine oil quality. Such a system would provide the operator with an accurate measurement of oil quality and an indication of whether or not the oil should be changed. Such a system will remove the uncertainties with regards to contaminant levels that are inherent in the presently used mileage- or time- based oil change schedules.